What happened
On the day of the occurrence, a PA-2im pilot attempted to take off from an occupied runway at Shellharbour. During the event, a Saab aircraft was backtracking along the same runway. The pilot of the PA-28 observed the Saab beginning a right turn on the runway but incorrectly assessed that the aircraft had already vacated the runway. Driven by self-imposed time pressure due to heavy traffic, the pilot proceeded with the takeoff roll without confirming the runway was clear. As the PA-28 climbed, the pilot detected the Saab still on the runway, prompting an emergency response that increased the risk of a collision. While braking calculations suggested there was sufficient distance to stop, the conflict had already been initiated.
The investigation
Investigators reviewed radio transmissions on the CTAF frequency, which revealed a high volume of traffic that increased workloads for both crews. The investigation found that the PA-28 pilot missed a critical radio transmission from the Saab crew, who had explicitly stated they were backtracking. This lack of communication was compounded by the use of non-standard phraseology by the PA-28 pilot during their runway entry, which was difficult to interpret. Furthermore, while the PA-28 pilot had previously flown at Shellharbour, their prior experience did not include full-stop landings, meaning they were likely unaware that larger aircraft like the Saab must use the runway to reach the apron.
Findings
- The PA-28 pilot failed to hear the Saab's backtracking announcement, which reduced situational awareness.
- The pilot incorrectly believed the Saab had cleared the runway after seeing it begin a turn.
- High traffic density at the airport created a busy radio environment that hindered effective communication.
- The pilot's decision to expedite the takeoff was influenced by pressure to manage the heavy traffic load.
- A lack of specific warnings regarding taxiway restrictions at the airport may contribute to pilots misidentifying aircraft that are backtracking as having vacated the runway.